test-fixing
💡 Summary
An AI skill that systematically identifies, groups, and fixes failing tests in a codebase.
🎯 Target Audience
🤖 AI Roast: “This skill is like a meticulous librarian who can sort your book returns by genre, but still needs you to write the missing chapters.”
The skill executes shell commands (`make test`, `uv run pytest`, `git diff`), which could be hijacked if the build process or test suite is maliciously modified. It also reads and writes files during the fix process. Mitigation: Run the AI agent in a sandboxed environment with restricted filesystem and network access, and audit the project's test commands before execution.
name: test-fixing description: Run tests and systematically fix all failing tests using smart error grouping. Use when user asks to fix failing tests, mentions test failures, runs test suite and failures occur, or requests to make tests pass.
Test Fixing
Systematically identify and fix all failing tests using smart grouping strategies.
When to Use
- Explicitly asks to fix tests ("fix these tests", "make tests pass")
- Reports test failures ("tests are failing", "test suite is broken")
- Completes implementation and wants tests passing
- Mentions CI/CD failures due to tests
Systematic Approach
1. Initial Test Run
Run make test to identify all failing tests.
Analyze output for:
- Total number of failures
- Error types and patterns
- Affected modules/files
2. Smart Error Grouping
Group similar failures by:
- Error type: ImportError, AttributeError, AssertionError, etc.
- Module/file: Same file causing multiple test failures
- Root cause: Missing dependencies, API changes, refactoring impacts
Prioritize groups by:
- Number of affected tests (highest impact first)
- Dependency order (fix infrastructure before functionality)
3. Systematic Fixing Process
For each group (starting with highest impact):
-
Identify root cause
- Read relevant code
- Check recent changes with
git diff - Understand the error pattern
-
Implement fix
- Use Edit tool for code changes
- Follow project conventions (see CLAUDE.md)
- Make minimal, focused changes
-
Verify fix
- Run subset of tests for this group
- Use pytest markers or file patterns:
uv run pytest tests/path/to/test_file.py -v uv run pytest -k "pattern" -v - Ensure group passes before moving on
-
Move to next group
4. Fix Order Strategy
Infrastructure first:
- Import errors
- Missing dependencies
- Configuration issues
Then API changes:
- Function signature changes
- Module reorganization
- Renamed variables/functions
Finally, logic issues:
- Assertion failures
- Business logic bugs
- Edge case handling
5. Final Verification
After all groups fixed:
- Run complete test suite:
make test - Verify no regressions
- Check test coverage remains intact
Best Practices
- Fix one group at a time
- Run focused tests after each fix
- Use
git diffto understand recent changes - Look for patterns in failures
- Don't move to next group until current passes
- Keep changes minimal and focused
Example Workflow
User: "The tests are failing after my refactor"
- Run
make test→ 15 failures identified - Group errors:
- 8 ImportErrors (module renamed)
- 5 AttributeErrors (function signature changed)
- 2 AssertionErrors (logic bugs)
- Fix ImportErrors first → Run subset → Verify
- Fix AttributeErrors → Run subset → Verify
- Fix AssertionErrors → Run subset → Verify
- Run full suite → All pass ✓
Pros
- Provides a structured, repeatable process for fixing tests.
- Prioritizes fixes by impact and dependency, improving efficiency.
- Reduces cognitive load by grouping similar errors together.
- Encourages minimal, focused changes to avoid regressions.
Cons
- Relies heavily on the project having a `make test` command, which is not universal.
- The strategy is generic and may not handle complex, interdependent test failures well.
- Assumes the AI has access to edit tools and a deep understanding of the codebase.
- May be less effective for flaky tests or tests with external dependencies.
Related Skills
claude-mods
A“Powerful, but the setup might scare off the impatient.”
Disclaimer: This content is sourced from GitHub open source projects for display and rating purposes only.
Copyright belongs to the original author mhattingpete.
